The need for cleaning pipes, particularly gravity drainage piping, is a recurring problem for technicians in the field. A method of pipe cleaning must entail a method of either removing an obstruction in a retrograde fashion to the pipe inlet or cleaning port, or else pushing the obstruction anterograde such that it can be carried away by flow within the pipe. The obstruction removal is obviously best conducted with a technique designed to minimize the danger of damage to the pipe itself. What has been needed but was heretofore unavailable is an apparatus to facilitate the cleaning of piping with commonly available vacuum sources such as high-vacuum industrial truck units as well as relatively low-vacuum shop vacuum devices.
In the past various methods have been employed to remove obstructions from piping systems. Perhaps the most traditional has been the use of a plumber's rod, often denominated a “snake,” as demonstrated in U.S. Pat. No. 4,317,247 to Levine. Such a tool features an enlarged end to the rod, which serves to manually engage the obstruction. Rotary force applied to the rod tends to either snag the obstruction for retrograde removal, or to manually break it up for anterograde flushing. Due to such method of operation, the tool is best utilized on obstructions that are either soft enough to be snagged by the tool, or friable enough to be broken up for flushing. Once friable obstructions are broken up they often simply accumulate at the next change of direction in the piping system and re-clog the piping. Obstructions formed by multiple discrete objects are less vulnerable to this approach, as the rod will tend to separate the obstructions without removing them, particularly when those multiple objects are hard in nature and cannot be snagged by the rod for retrograde removal. In such a situation, obstructions will be churned, but are likely neither to be removed retrograde nor pushed through the pipe. Multiple small obstructions, by way of example and not limitation, such as multiple small pieces of metal, can be particularly problematic in pipes transmitting high viscosity fluids, where the obstruction to flow posed by such objects is the greatest. This is particularly problematic in automotive repair garages and the drains of similar industrial locations.
An alternative approach to pipe obstruction removal is demonstrated by U.S. Pat. No. 6,013,138 to Sinz. In the Sinz '138 device, a length of tubing is passed through the lumen of the pipe, proximal to the obstruction, and a stream of water is directed from the end of the tubing to apply mechanical force to break up an obstruction. A vacuum apparatus is applied at the top of the pipe to remove both the flushing water and the broken up pieces of the obstruction. This removal method has the disadvantage of requiring the vacuum removal of water or some other relatively high-density solvent used to mobilize the obstruction, and any air, which is very low in relative density, which is entrained proximal to the obstruction will severely hamper vacuum effectiveness. Any leak in the vacuum seal will tend to preferentially entrain air over solvent, and will preferentially entrain air in regard to removal of debris. This effect is exacerbated as the relative density difference between atmospheric air and the density of the debris increases, i.e., the more dense the obstructions, or the multiple objects making up an obstruction, the more preferentially will air be entrained.
Vacuum systems, such as that described by Sinz '138, have failed to provide positive methods for avoiding this entrainment of air. The problem is made more difficult by the fact that pipe entrances may be encountered in a plurality of sizes; shapes; and design possibilities, such as the various sizes and shapes of floor drains and cleanouts for gravity drainage systems as well as the various sizes and pipe joining methods for process, hydronic, domestic water, fire protection and the multitude of other piping systems.
Accordingly, the art has needed a means for providing a positive vacuum seal at a plurality of pipe sizes and configurations, without rigid adaptors and without damaging the inlet of the piping system, while facilitating its use with commonly available vacuum sources. Therefore, what continues to be needed but is missing from the field of pipe cleaning tools is an apparatus for creating a positive vacuum seal between a vacuum source and a piping system that is designed for ease of use and manufacture. While some of the prior art devices attempted to improve the state of the art of pipe cleaning tools, none has achieved a cost optimized capability that is easy to fabricate and convenient to use with a wide variety of vacuum sources and piping systems. With these capabilities taken into consideration, the instant invention addresses many of the shortcomings of the prior art and offers significant benefits heretofore unavailable.